1. Field of the Invention
This invention relates to variable color display devices utilizing light emitting diodes.
2. Description of the Prior Art
The difficulty of rapidly detecting the presence of a decimal point in a long string of digits, displayed on a multi-element digital display which includes a large number of display segments, is appreciated in the prior art.
A monochromatic multi-digit display disclosed in U.S. Pat. No. 3,719,849, issued on Mar. 6, 1973 to Robert L. Stewart, dedicates one digit position to a decimal point. When a string of digits is displayed, only the decimal point is energized on one display digit to provide wide separation between the decimal point and its nearby digits, for improving the readability of the decimal point in a long string of digits.
An electronic display having segments wherein each segment is capable of selectively illuminating two colors is disclosed in U.S. Pat. No. 4,488,149 issued on Dec. 11, 1984 to William A. Givens, Jr. Two AND gates are provided for biasing, in each display segment, either a first light emitting diode, for emitting a first color, or a second light emitting diode, for emitting a second color. It is not contemplated to illuminate both light emitting diodes in each segment simultaneously for blending the colors.
The prior art does not contemplate a display system for automatically exhibiting integers and decimal numbers in different colors.